Process for waterproofing and strengthening threads and fabrics



- UNITED STATES PATENT, OFFICE.

LOUIS GABRIEL RAYMOND AUZENAT, OF PARISQFRANCE, ASSIGNOR TO LA LOIE ARTIFICIELLE DE LA VOULTE OI TARIS, FRANCE.

PROCESS FOR WATERPROOFING 1T0 Drawing.

To all whom it may concern:

Be it known that I, LOUIS GABRIEL BAY- MOND AU'ZENAT, citizen of the Republic of France, and resident of Paris, France, (post-office address, 16 Rue du Louvre,) have invented a new and useful Process for Waterproofing and Strengthening Threads and Fabrics, which improvements are fully set forth in the followlng specification.

It is known that the tensile strength of a thread of vegetable origin diminishes very considerably when the thread is moistened.

- This drawback is particularly serious when the material in the State of a thread or fabric will have to stand tensile-stresses dur ng or after washing.

The present invention has for its object to maintain the i strength of the material while in the moist state, and thus impart thereto one of the most appreciated properties of natural silk. I

Various attempts hitherto made in thls direction have been faced with the difficulty of covering each of the small filaments composing the -thread 'with an impermeable layer, without causing the filaments to st ck together, that is to say, without destroying the resilience of the thread.

In the-treatment of skeins, hanks or bundles, in suitable baths, not only do the filaments, but the threads themselves, stick together and the material thus becomes unwindable. The only practicable method is the treatment thread by thread, but this is only suitable in the case Where there is no need for the thread to be resilient, and the costs of the treatment are very high.

It has also been proposed to use filaments of waterproof material, such as organic cellulose esters, but unlike threads of pure cellulose, these threads do not absorb the ordinary dye baths and require special and very costly processes, are rarely satisfactory.

In order to remedy these defects of procedure, and at the same time reduce the working costs'to a minimum, according to the present invention,-the thread is treated in bulk with substances in the gaseous state. These must be in such a state of dilution that they can easily and completely penetrate the material to be rendered impermeable without being deposited on the surface in a thickness sufficient to cause the threads to stick together. The sole part that these Specification of Letters Patent.

the. results of which AND STRENGTHENING 'rrmnans'ann snares.

. Patented May a, 1921.

Application filed 11111211 25, 1920. Serial no. 368,775.

to the solid state, is, to fill the capillary pores in the interior of the filament, so that ence of water. At the same time the sup- 'pleness of the thread is not afi'ected, nor

is there any measurable increase in density. The quantity of substance to be introduced into the fabric should, therefore, always be as small as possible.

It is evident that since thread, waterproofed in this manner, can no longer be dyed 1n the usualway, the treatment must be applied to a thread already dyed.

The substances suitable for use in this method are all those than can be transformed into a gas or vapor, and then react upon each other in that state, at'below the decomposltlon temperature of cellulose, a'

partial vacuum being employed if neces-- sary. By way of example, the reaction of ozonized alr upon oil of turpentine or that of formaldehyde upon henols and the like may be mentioned. W ere the reaction requires the presence of anacid, the use of organic acids of high vapor tension such as formlc acid or acetic acid is articularly indlcated. The substances to e brough into reaction may be introduced simultaneously or successively.

In order, more particularly, to describe the method of applying the process, the deposition of resin in the interior of a fiber 1s glven by way of example.

In an autoclave, provided with a heating jacket, hanks of dyed and dried artificial s1lk, are suspended in such away that no portion is compressed and consequently the whole is open to uniform penetration by' vapor. The temperature being maintained at about 100 C., and the pressure of the atmosphere inside the autoclave being reduced to about 5 centimeters of mercury gage, the autoclave is connected to a vessel containing oil of tur entine. This vessel is then heated and w en the pressure has risen to 15 centimeters of mercury gage in the autoclave the connection with the turpentine vessel is cut off. The autoclave being kept closed, the tur entine vapor is allowed to penetrate into tlie thread for two hours, the temperature being allowed to fall gradually to that of the external air. At this point communication is'very gradu:

, gases or vapors should fulfil on their return 7 the atmosphere by means of a tube, wherein the entering air is strongly ozonized, for

- be carried out under the -t10I1 given above,

example,

lamp. fter remaining for two hours in this ozonized air, during which time the reaction proceeds uniformly throughout the threads, the autoclave is opened and the thread is taken out and thoroughly shaken.

After being left in the outer air for 24' artificial silk may .be The treatment may same conditions by admittingacetic acid'vapor into the auto clave, along with the turpentine vapor.

i The process is applicable towoven fabric as well as to skeins of thread.

It is furthermore evident that the invention is not limited to the mode of operathis being simply by way of example of the manner in which the general process may be carried out.

What I claim and desire to secureby Letters Patent of the United States is l. A process of waterproofing and strengthening threads and fabrics, the tensile strength of which decreases in the moistened state, consisting in subjecting the threads or fabrics to the action of at least two substances in a gaseous state, said substances reacting upon each other while in such state to synthetically form compounds impenetrable to water.

2. Process for waterproofing and strengthening threads and fabrics, the tensile strength of which diminishes in the moistened state, consisting in treating the threads and fabrics. with vapors of phenol and subsequently with vapors of formaldehyde.

3. Process for the waterproofing and hours, the hanks of made up into packets.

by contact with a mercury vapor to the action strengthening of threads andv tensile strength of which diminishes in the moistened state, consisting in treating the threads and fabrics with vapors of phenol and subsequently with vapors of formic acid ,and formaldehyde. 7

4. A process of waterproofing and strengthening threads and fabrics, the tensile strength ofwhich decreases in the moistened state, consisting in initially subjecting the threads or fabrics for a period of time to the action of a substance in a gas eons state so as to enable said substance to penetrate into thethreads or fabrics, and

thereafter subjecting the threads or fabrics gaseous state -which will react while in such state upon the first substance to form compounds impenetrable to water.

v process of waterproofing and strengthening threads and fabrics, the tensile strength of which decreases in the moistened state, consisting in initially subjecting the threads or fabrics for a period of time to the action of a substance in a gaseous state and in a'heated atmosphere, allowing the temperature to fall graduallyto that of the external air, and thereupon subjecting the threads or fabrics to the action of a second substance in a gaseous state which will react while in such state upon the first substance to form compounds impenetrable to water.

In testimony whereof I have signed this specification in the presence of a subscribing witness.

LOUIS GABRIEL RAYMOND AUZENAT, Witness: I

FERNAND DUFoU fabrics, the

of a second substance in a 1 

